The San Joaquin River that passes Manteca and Lathrop just as it reaches the Delta is ground zero for yet another fight over water.
This time it’s to reduce the growing threat of toxic algal bloom in the Delta that pose a threat to humans and pets alike.
And if emergency petitions filed last month with the State Water Control Resources Board succeed, it will throw a major wrench into state efforts to deal with allocating dwindling water supplies as California enters its fourth year of drought.
It is the latest threat to regional water supplies intertwined with Delta issues that include:
*A push to increase fish flows on the Stanislaus, Tuolumne and Merced watershed.
*Salinity intrusion issues — both in surface water and groundwater below the Delta — that could occur if a diversion tunnel from the Sacramento River to the California Aqueduct pumping stations northwest of Tracy is built.
*Minimum fish flows and oxygen levels as measured at Vernalis at the confluence of the Stanislaus and San Joaquin rives in order to protect fish in drought conditions.
The petition seeks to pump up the seasonal flow into the Delta from the San Joaquin River to 40 percent.
Baywatchers, that is among the groups filing the petition, indicated such a flow was included in the update Bay-Delta plan several years ago.
Experts concluded not only would the 40 percent flow help fish but it could flush out organisms in the Delta causing the agal bloom.
The problem with water coming from the San Joaquin River to do that is simple.
It wasn’t until several years ago that water flowing from the headwaters of the San Joaquin River ever had a chance of reaching the Delta as it did 60 plus years ago.
That’s because until diversion agreements were changed nearly 50 miles of the river ran dry after it passed Fresno.
Even now, water flows are at a minimal.
That means whatever water is needed to obtain a 40 percent flow would have to come from the three rivers that feed into the San Joaquin River as it nears the Delta — the Stanislaus, Tuolumne and Merced.
It's a move that some researchers believe could help fish and wildlife and potentially flush out the organisms causing the bloom.
Water on those three watersheds are committed via historic water rights and agreements to serve the needs of the northern San Joaquin valley in addition to established fish flows.
That means water to accomplish the 40 percent flow would have to be wrangled from existing users.
The Baywatchers and other groups were spurred to file the emergency petition by a destructive agal bloom this past summer in the San Francisco Bay.
Microorganism that cause the agal bloom have been detected in the Delta near Discovery Bay as well as Stockton.
"It produces a toxin that's acutely poisonous to people and their pets. So, this, this will kill your dog if it gets exposed to enough of it and can make people very sick if they come in contact with a water. But also, the toxins and the cyanobacterial cells get aerosolized in a heavy wind. So, it makes it sort of a hazard, even if you're walking near the waterway," Jon Rosenfield, senior scientist with San Francisco Baykeeper told a San Francisco TV Channel 7 news.
Study: 1,103 more Chinook salmon
will cost North SJ Valley $12.9B
The petition would appear to add ammunition to a 2018 state study conducted to justify increased water flows to help boost the endangered Chinook salmon on the Merced, Tuolumne, and Stanislaus rivers.
Sacramento concedes the increased water flows may only increase Chinook salmon numbers in the Stanislaus, Merced, and Tuolumne rivers by 1,103 while at the same time delivering devastating blows to the economies of San Joaquin, Stanislaus and Merced counties.
The state’s own data says the tradeoff for 1,103 more fish could take 132,000 acres out of farm production, cause a $12.9 billion annual reoccurring loss to the three-county region, eliminate 4,000 jobs, and further imperil the groundwater by forcing cities and farms to pump 1.57 million acre feet — the equivalent of just over three-fifths of New Melones Reservoir when it is filled to the brim.
The South San Joaquin Irrigation District that delivers water to 230,000 water users in Manteca Tracy, Lathrop and Mountain House as well as other water agencies in the Lower San Joaquin River tributaries believe a holistic approach that takes into account all factors such as water flows, non-native predators, and habitat is the best solution as opposed to a myopic one that relies 100 percent on jacking up water releases.
That’s because while the fish flows are aimed at salmon movements in the Stanislaus, Tuolumne and Merced rivers the additional water flowing into the Delta will allow flows mandated from the Sacramento Valley watershed needed to assure a set level of water quality in the Delta to be scaled back.
By taking water from urban and ag users served by the three rivers, it allows dams that serve the massive Metropolitan Water District and even some Bay Area cities to keep more water in storage needed for their use.
And while the state and/or federal government contends the water they plan on releasing for pumped up fish flows isn’t targeting water the SSJID and other agencies with historic legal rights that are adjudicated, once water levels in storage facilities drop to critical levels and there is a need to meet minimum river flows they only have one option to prevent an ecological disaster which is outright seizing local water.
The SSJID and Oakdale Irrigation District have commissioned extensive studies on the Stanislaus River by Fishbio, a scientific research firm with a global resume. The two agencies have been conducting research for more than a decade to develop data regarding everything from water temperature and water flows as well as predators on the impact in threatened salmon on the Stanislaus. The state hasn’t done any such studies on the Stanislaus or the Merced and Tuolumne.
OID has gone a step further and invested more than $1 million on enhancing spawning areas for salmon along the Stanislaus.
To contact Dennis Wyatt, email dwyatt@mantecabulletin.com
